Abstrakt

Design and Implementation of SHE PWM in a Single Phase A.C.Chopper Using Generalized Hopfield Neural Network

Prof.M.Balasubramonian, S. Dharani

In this paper, an implementation of Selective Harmonic Elimination Pulse Width Modulation (SHEPWM) as applied to a single phase AC chopper using Generalized Hopfield Neural Network (GHNN) is designed and implemented. The objective of this paper is to eliminate 5, 7, 11, 13 th order harmonics in the output voltage waveform of the AC chopper while retaining fundamental component to the desired value. The switching angles corresponds to the above objective are obtained by solving a set of non-linear algebraic transcendental equations. The problem is redrafted as an optimization problem and it is solved by using GHNN. An energy function is formulated for the above problem and a set of differential equations describing the behavior of GHNN were formed by using the derived energy function. These set of differential equations are stiff in nature and it is numerically solved by the semi-implicit midpoint rule based extrapolation method with suitable initial conditions. The initial conditions are obtained from a look up table. A MATLAB simulation was carried out and the FFT analysis of the simulated output voltage waveform confirms the effectiveness of the proposed method. Hence, the proposed method proves that it is much applicable in the industrial applications.